Research On Maintenance Interval Optimization Strategy Model Of Gas Turbine Passage Parts

Because of its high efficiency and low pollution, combined cycle power plants (CCPP) have been applied all over the world. As the key component of CCPPs, the performance of gas turbines plays a decisive role in the operation condition of CCPPs.About the problem of compressor inlet filtration update and gas turbine crank washing, some optimal methodologies were put forward in this paper.The inlet filtration of gas turbines can effectively filter most of particle pollutants and this will decrease the performance deterioration rate of compressors. But with the increment of operating time, the pressure drop of filtration will increase as well, which will reduce the power output and efficiency of gas turbines. In view of this, based on the principle of minimum cost in the whole life cycle, a novel calculation methodology about optimal update interval was proposed. The calculation of a CCPP indicates that the optimal update interval is approximately6800hours. Compared with the being executed (3300hours), the novel methodology mentioned above could save production cost1.35million Yuan per year. Also, effects of initial cost, fuel price and market electricity price on optimal update interval were studied.Simultaneously, based on the principle of minimum mean generalized crank washing cost in the whole crank washing interval, a novel optimization model about economical crank washing interval was proposed. The generalized crank washing cost mainly includes running additional cost and shutdown cost. The calculation of a heavy-oil-fired and a gas-fired CCPP indicates that the optimal crank washing interval is respectively77and423hours. Compared with the actual interval being executed by the power plant, the optimization model mentioned above profited more respectively12.34and10.12million Yuan per year. Finally, effects of fuel price, market electricity price, shutdown time, degradation rate and washing number on optimal crank washing interval were studied also. The conclusions obtained have certain reference value to inlet filtration update interval and crank washing interval of other CCPPs.